1. Technical Field
This application relates to surgical staplers, and more particularly, to an apparatus for sequentially applying a plurality of surgical fasteners to body tissue.
2. Background of Related Art
Surgical devices wherein tissue is first grasped or clamped between opposing jaw structure and then joined by means of surgical fasteners are well known in the art. In some instruments a knife is provided to cut the tissue which has been joined by the fasteners. The fasteners are typically in the form of surgical staples however, two part polymeric fasteners are also utilized.
Instruments for this purpose can comprise two elongated members which are respectively used to capture or clamp tissue. Typically, one of the members carries a cartridge which houses a plurality of staples arranged in at least two lateral rows while the other member comprises an anvil which defines a surface for forming the staple legs as the fasteners are driven from the cartridge. Where two part fasteners are used, this member carries the mating part, e.g. the receiver, to the fastener driver from the cartridge. Generally, the stapling operation is effected by a pusher which travels longitudinally through the cartridge carrying member, with the pusher acting upon the staples to sequentially eject them from the cartridge. A knife may travel with the pusher between the staple rows to longitudinally cut and/or open the stapled tissue between the rows of staples. Such instruments are disclosed in U.S. Pat. Nos. 3,079,606 and 3,490,675.
A later stapler disclosed in U.S. Pat. No. 3,499,591 applies a double row of staples on each side of the incision. This is accomplished by providing a cartridge assembly in which a cam member moves through an elongate guide path between two sets of staggered staple carrying grooves. Staple drive members are located within the grooves and are positioned in such a manner so as to be contacted by the longitudinally moving cam to effect ejection of the staples. Other examples of such staplers are disclosed in U.S. Pat. Nos. 4,429,695, 5,065,929, and 5,156,614.
Many of the prior art linear stapling devices discussed above include a significant number of moving parts, small components and machined structural elements that are costly to fabricate and time consuming to assemble. These factors add to the overall cost of the stapling devices and thus increase the costs incurred by hospitals and health care professionals, and ultimately, the patient upon which the devices are utilized. It would be advantageous to provide a linear stapler that could be manufactured and assembled less expensively. It is also known that prior art linear stapling devices are specifically designed to apply staples rows of only one length. The linear staplers which are reloadable are configured to only receive a fresh array of staples of a fixed length. Thus, in surgical procedures requiring the placement of staple rows of varying length, it is necessary to employ different staplers, which, adds to the overall cost associated with the operation. It would be advantageous to provide a stapler which could be reloaded with varying length staple arrays to enable the application of staple rows of differing length to body tissue using a single stapler.